A. Field of the Invention
This invention relates in general to an apparatus and method for assembling optical path folding devices. More particularly, the present invention relates to an apparatus and method for manufacturing low cost, precision optical devices which utilize single or multiple bounces.
B. Prior Art
In the prior art, various assemblies have been utilized to mount and align optical mirrors for use in single or multiple bounce optical path folding devices.
FIG. 1 shows one prior art system utilized to mount and align mirrors. In this system, the assembly 10 is formed from two identical subassemblies 12 which are joined together by appropriate means along the overlapping portions of frame members 14. A mirror holding member 16 is pivotably mounted to support 18 as shown. A mirror 20 is bonded to each mirror holding member 16 by means of a suitable adhesive 22. In such a prior art system, each mirror 20 may be pivoted in order to achieve accurate optical alignment.
The prior art system of FIG. 1 suffers from two major drawbacks. The system is mechanically complex and its production cost is not appropriate for use in low cost optical systems. The second drawback is in the time consuming and therefore costly alignment procedures required to achieve accurate optical alignment of the mirrors 20.
FIG. 2 shows another prior art system known as replication. Replication is typically used in precision optic devices where repeatability and large production quantities are required. In this system, a reflective coating 26 is bonded via an adhesive to a precision machined surface 28 on holding structure 30. The reflective coating 26 is very thin and of a uniform thickness. The quality of the surface 28 reflects the quality of the mirrored surface obtained after the reflective coating 26 is bonded to surface 28. Therefore, the surface 28 to which the coating 26 is bonded must be accurately machined to assure optical alignment of the completed assembly. The main drawback of replication is that the process is costly and time consuming.
It is the general object of the present invention to overcome the above-mentioned drawbacks of the prior art by providing an improved apparatus and method for assembling folded optical path folded mirror systems.
It is another object of the present invention to provide a repeatable and low cost method and apparatus for producing precision aligned folded optical path mirror systems.
It is a further object of the present invention to provide a method and apparatus for assembling folded optical path mirror optical systems without the need to adjust the mirrors for proper alignment.
It is an additional object of the present invention to provide an apparatus and method for producing optical mirror systems utilizing inexpensive mechanical substrates.
These and other objects, features and advantages of the present invention will become more apparent from the detailed description of the preferred embodiment when read in conjunction with the drawings.